title: Repeated magnetic resonance imaging and cerebral performance after cardiac arrest--a pilot study.
abstract: OBJECTIVE
  Prognostication may be difficult in comatose cardiac arrest survivors. Magnetic resonance imaging (MRI) is potentially useful in the prediction of neurological outcome, and it may detect acute ischemia at an early stage. In a pilot setting we determined the prevalence and development of cerebral ischemia using serial MRI examinations and neurological assessment.
  
  
  METHODS
  Ten witnessed out-of-hospital cardiac arrest patients were included. MRI was carried out approximately 2h after admission to the hospital, repeated after 24h of therapeutic hypothermia and 96 h after the arrest. The images were assessed for development of acute ischemic lesions. Neurophysiological and cognitive tests as well as a self-reported quality-of-life questionnaire, Short Form-36 (SF-36), were administered minimum 12 months after discharge.
  
  
  RESULTS
  None of the patients had acute cerebral ischemia on MRI at admission. Three patients developed ischemic lesions after therapeutic hypothermia. There was a change in the apparent diffusion coefficient, which significantly correlated with the temperature (p < 0.001). The neurophysiological tests appeared normal. The patients scored significantly better on SF 36 than the controls as regards both bodily pain (p = 0.023) and mental health (p = 0.016).
  
  
  CONCLUSIONS
  MRI performed in an early phase after cardiac arrest has limitations, as MRI performed after 24 and 96 h revealed ischemic lesions not detectable on admission. ADC was related to the core temperature, and not to the volume distributed intravenously. Follow-up neurophysiologic tests and self-reported quality of life were good.
authors.affiliation: Department of Anaesthesia and Intensive Care, Haukeland University Hospital, Bergen, Norway. baard.heradstveit@helse-bergen.no
authors.forename: Bård E
authors.initials: BE
authors.lastname: Heradstveit
authors.forename: Elna-Marie
authors.initials: EM
authors.lastname: Larsson
authors.forename: Håvard
authors.initials: H
authors.lastname: Skeidsvoll
authors.forename: Stig-Morten
authors.initials: SM
authors.lastname: Hammersborg
authors.forename: Tore
authors.initials: T
authors.lastname: Wentzel-Larsen
authors.forename: Anne Berit
authors.initials: AB
authors.lastname: Guttormsen
authors.forename: Jon-Kenneth
authors.initials: JK
authors.lastname: Heltne
mesh_terms: D000328:Adult; D000368:Aged; D002545:Brain Ischemia / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D016887:Cardiopulmonary Resuscitation; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D007362:Intensive Care Units; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D010865:Pilot Projects; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D020127:Recovery of Function; D013997:Time Factors; D055815:Young Adult